The March Night Sky 2019

Article by: Helen McLoughlin, Education Officer

How is it March already? 2019 has just flown in! Although we have had a mild winter, we can start to wave goodbye to the dark evenings and say hello to Spring as the date that I have been longing for ever since the evenings got shorter – the Spring Equinox on the 20th March fast approaches. After this date, the Sun moves up to shine over the Northern Hemisphere, so the days become longer than the nights (thank goodness)! This is closely followed by the official start of British Summer time on 31st March. Unfortunately, that does not promise the sun splitting the sky and record-breaking temperatures, but it does mean that our evenings will begin to stretch out before us. This does come at a price though as we lose one precious hour in bed as the clocks spring forward.

Orion is visible in both the Northern and Southern hemispheres. In the Northern hemisphere the constellation can be seen from late autumn to early spring. In the Southern hemisphere Orion can be seen in the summer months, note that it will appear upside down. Image Credit: Heather Alexander/Stellarium/Armagh Observatory and Planetarium

This month is also your last chance to see Orion the Hunter and Canis Major as they start to disappear below the horizon. They can be spotted looking South West in the sky during month. You can use the three stars of Orion’s belt to find the brightest star in the night sky, Sirius. Draw an imaginary diagonal line downwards from Orion’s belt and it’s hard to miss Sirius twinkling in the night sky. So, make sure you get out and admire these constellations before they disappear for another year.

Look for Leo (Image credit: Armagh Observatory and Planetarium/Stellarium)

Although we will be saying goodbye to these well-known stars and constellations, with a new season, comes new treasures in the night sky. For example, Leo the Lion is now in full view, which means Regulus, also known as the ‘heart’ of the Lion, appears bright in the sky. This star is around 79 light years away and throws out about 300 times as much energy as our local star, the Sun. It is bluey white in colour as it is relatively young (approximately a billion years old so just one-fifth the age of the Sun) and in early March it ascends in the East. Regulus can be found marking the bottom of a large backwards question mark star pattern within Leo, known as The Sickle.

Something harder to spot, but well worth it if you do find it, is the The Praesepe (or Beehive) star cluster found in the heart of the constellation Cancer the Crab. Cancer is a much fainter constellation than the likes of Leo, but here are a few tips to help find this star cluster. First, find Regulus and the stars that mark the heads of Castor and Pollux, the Gemini twins. The Beehive is halfway between these stars. Unfortunately you cannot see this star cluster with the naked eye, however with the help of binoculars you can explore this cluster in more detail. There are known to be 1000 stars in the cluster, two of which are circled by planets. With binoculars, you might notice two bright stars on either side of the cluster. In skylore, they represent the donkeys that Dionysos and Silenus rode into battle against the Titans.

Image of mercury by messenger
Time and space-warped planet: Mercury has a bleak majesty to its landscapes (image credit: NASA, JHU APL)

More good news for March – more sightings of planets! The lesser spotted Mercury can be seen at the start of March, looking low on the horizon towards the west at dusk, you should be able to see Mercury shining at a magnitude +0.1 and setting around 7.30pm. The return of the red planet to our skies is the one I’m most looking forward to, particularly when Mars forms a lovely sight next to the Pleiades during the last couple of nights of March.

Another exciting event occurs on 21st March – the last supermoon of 2019! The Moon will be at its closest approach to the Earth and if we get a clear, dark night it should look slightly larger and brighter than usual.

Happy star/planet/moon gazing everyone!